Estimacao pontual dos coeficientes de repetibilidade e reprodutibilidade em ensaios interlaboratoriais

Abstract

This dissertation studies punctual estimators of the repeatability coefficient (r) and l eproducibility coefficient (R) in interlaboratory test. Assuming a linear balanced model with gandom effects corresponding to the laboratories, four estimators based on variance component are considered. The estimators were the moment, the truncated one, the Inaximum likelihood and the residual maximum likelihood. The exact joint distribution of the estimators r and R are obtained, as well as, their moments, biases, and mean square errors. Ir he performance of the estimators was illustrated using a interlaboratory study conducted to gletermine thickness of tin plates.